Composition and abundance of benthic macroinvertebrates in Lake Kyoga system, Uganda

Study Extent

The datasets present data for surveys conducted between 1999 and 2017.

Sampling

A ponar grab with an open jaw area of 238 cm2 was used to take samples of benthic macroinvertebrates. One to three hauls were taken from each sampling point. When more than one haul was taken, they were mixed to form a composite sample. The bottom type at each point was described from the grabbed contents. This was captured as location remarks. Samples were concentrated and then placed in labeled sample bottles and preserved with 5% formalin solution. In the laboratory, each sample was rinsed with water and then placed on a white flat-bottomed tray. Macro-invertebrates were sorted, and individual taxa identified to the lowest possible taxonomic level using identification keys (Mandahl-Barth, 1954), Pennak, 1953), Merritt and Cummins, 1997, De Moor et al. 2003). All taxa were recorded, and individuals of each taxon enumerated to estimate their densities.

Quality Control

The samples were immediately processed in the field and treated with formalin to keep the organisms of interest intact. To avoid loss of organisms during sample processing, nets with appropriate mesh sizes were used.

Method steps

1. Collection of the macroinvertebrates In the field, sediment samples were collected using a ponar grab with an open jaw surface area of 238 cm2. At each site, three sediment samples were obtained. The three samples were mixed and concentrated to form one composite sample for each site.
2. Preserving the samples The composite sample for each site was separately preserved in 5% formalin to maintain the organisms in good condition prior to analysis in the laboratory.
3. Identification of macroinvertebrates In the laboratory, formalin was rinsed off from each sample and placed in white flat-bottomed trays. Using pairs of forceps, all benthic macro invertebrates were sorted from the sediment and the individual taxa identified to the lowest possible taxonomic level using appropriate identification keys and a dissecting binocular microscope at 4x 25 magnification.

Aquatic macroinvertebrates identified to order, class, family, genus, species and subspecies

1. Ablabesmyia Johannsen, 1905
   rank: genus
2. Anisoptera (Selys, 1854)
   rank: order
3. Baetidae
   rank: family
4. Bellamya Jousseaume, 1886
   rank: genus
5. Biomphalaria (Preston, 1910)
   rank: genus
6. Bivalvia
   rank: class
7. Bulinus (Müller O.F., 1781)
   rank: genus
8. Byssanodonta d'Orbigny, 1846
   rank: genus
9. Caenis Stephens, 1835
   rank: genus
10. Caridina nilotica (P.Roux, 1833)
    rank: species
11. Ceratopogonidae
    rank: family
12. Chaoborus A.A.H.Lichtenstein, 1800
    rank: genus
13. Chironomidae
    rank: family
14. Chironomus Meigen, 1803
    rank: genus
15. Clinotanypus Kieffer, 1913
    rank: genus
16. Clitellata
    rank: class
17. Cloeon Leach, 1815
    rank: genus
18. Coelatura cridlandi G. Mandahl-Barth, 1954
    rank: species
19. Coelatura hauttecoeuri kyogae G. Mandahl-Barth, 1954
    rank: subspecies
20. Coelatura monceti (J.R. Bourguignat, 1883)
    rank: species
21. Coleoptera
    rank: order
22. Corbicula
    rank: genus
23. Corbicula fluminalis africana (F.Krauss, 1848)
    rank: subspecies
24. Corixidae
    rank: family
25. Cryptochironomus Kieffer, 1918
    rank: genus
26. Ecnomidae Ulmer, 1903
    rank: family
27. Ecnomus McLachlan, 1864
    rank: genus
28. Elmidae Curtis, 1830
    rank: family
29. Gabbia Tryon, 1865
    rank: genus
30. Gabbiella humerosa von Martens, 1879
    rank: species
31. Hirudinea
    rank: class
32. Laevicaudata Linder, 1945
    rank: order
33. Lanistes carinatus
    rank: species
34. Leptoceridae
    rank: family
35. Libellulidae
    rank: family
36. Melanoides (Olivier, 1804)
    rank: genus
37. Melanoides tuberculata (O. F. Müller, 1774)
    rank: species
38. Mutera Scopoli, 1777
    rank: genus
39. Ostracoda
    rank: class
40. Palpomyia Meigen, 1818
    rank: genus
41. Palpomyia tibialis (Meigen, 1818)
    rank: genus
42. Pisidium pirothi Jickeli, 1881
    rank: species
43. Povilla adusta Navás, 1912
    rank: species
44. Procladius Skuse, 1889
    rank: genus
45. Sphaerium Scopoli, 1777
    rank: genus
46. Tanypodinae
    rank: genus
47. Tanypus Meigen, 1803
    rank: genus
48. Tanytarsus Wulp, 1874
    rank: genus
49. Trichoptera
    rank: order
50. Trombidiformes
    rank: order

The Lake Kyoga system in Uganda comprises lakes Kyoga and several small lakes that form the Lake Kyoga system. The water bodies in the system are described in detail in Mwanja et al (2001).